Simplified Methodology of Economic Evaluation of Household PV Instalations in Czech Republic Using Monte Ccarlo Method

Abstract

his paper deals with the design of a suit- able, transparent, and reasonably accurate methodology for the economic evaluation of household photovoltaic (PV) installations in the Czech Republic. The basis of economic evaluations of household photovoltaic instal- lations is a time model of energy balance from which cash flows result. Therefore, a specific methodology of the energy balance calculation is proposed to increase accuracy, while at the same time, reasonably increas- ing the energy balance model complexity by using the Monte Carlo method (probability model). Following the detailed analysis of the affecting factors and the compi- lation of the methodology for the energy balance calcu- lation, the main stochastic parameters were specified. These specified stochastic parameters are estimated by the Monte Carlo method in multiple scenarios. The presented methodology of the energy balance calculation is also used for direct calculation where the mean val- ues of the same specified stochastic parameters (without assumption of their probability) serve as the reference values for one scenario. Pros and cons of the designed methodology are demonstrated in a case study of an existing household photovoltaic installation. The mean values of the output parameters from the Monte Carlo method scenarios are then calculated for subsequent re- sults comparison of both methods and also with the real (measured) values of the case study installation. Then a cash flows for each year of the installation’s lifetime are stated, and the internal rate of return (IRR) as an economic evaluation criterion is calculated. The results show that IRR differs between methods by about 2.5% which may be crucial in such long-term projects on the verge of profitability. The accuracy of the application of the Monte Carlo method to the output parameters is then discussed in the conclusion where some possible recommendations for further work and project evalua- tors are indicated as well.